Coupler knuckle



Feb. 18, 1964 N, H SUDECK 3,121,498

COUPLER KNUCKLE Filed 001C. 8, 1962 4 A l INVENTOR. j/ 5.3 Byeman, Y JJ/ United States Patent O 3,l2i,493 CQUIPLER KNUCKLE Norman lli. Sudeck, Aliiance, Unio, assigner to Arrested industries Incorporated, Chicago, lll., a corporation of New `lersey Fited Oct. 8, i962, Ser. l To. 236,319 1 Claim. (Cl. Z13-52) This invention relates to couplers and, more particularly, to couplers of the type which employs a knuckle pivotally connected to a coupler head. An example of such a type, and in which this invention is illustrated, is the alternate standard type F interlocking coupler of the Association of American Railroads.

This application is a continuation-impart of co-pending application Serial No. 29,055, tiled May 13, 1960, now abandoned.

The type of coupler commonly employed by rail traveling vehicles utilizes a knuckle pivotally supponted in a coupler head. The knuckle is engageable with a similar knuckle of a mating coupler. Under normal railway service conditions, the knuckle is subjected to heavy irnplacts. Occasionally, when shunting the cars, the coupler knuckle is accidentally or inadvertently left in 'the locked posi-tion. Upon impact of such a coupler with the mating coupler, the full force of the impact may be absorbed by the knuckle itself. Under such impacts, the coupler structure very commonly fails and, generally, the fail-ure occurs in the immediate vicinity of the pivotal connection of the knuckle to the coupler head.

An object of this invention is to provide mutually dependent means on the knuckle and coupler head, respectively, to absorb impact loads of buing thereby substantially eliminating structural failure of the coupler resulting therefrom.

A funther object of the invention is to provide increased areas of engagement between the knuckle and coupler head by means of novel mutually engaging steps annularly disposed thereon, respectively.

These and other objects `and advantages will become appare-nt from a consideration of the following specification and the accompanying drawings, wherein:

FIGURE l is a top plan view of a coupler head, with a portion of the top wall of the head out away, showing a knuckle therein employing an embodiment of the invention;

FlGURE 2 is a section view on line 2-2r of FlGURE l.

Certain details have been omitted from each figure where they are believed :to be adequately shown in the other figure.

Referring to the drawings, a coupler head, generally designated itl, comprises vertically spaced walls 12 interconnected by side walls 1d forming therebetween a cavity 16. An interlocking wing i8 projects forwardly of coupler head i@ on one side thereof; and la winged slot i9, for receiving the intenlock-ing wing of a mating coupler (not shown), is formed by pontions of side walls 14 on the other side thereof. A shelf 17 :is centrally located between side walls le and beneath cavity 16 to serve as a support for the head of a mated coupler (not shown). Ears 2- 4are disposed on coupler head it) intermediate win g i8 and slot i9. Substantially cylindrical bosses 22 project inwardly from ears Ztl and have substantially vertical surfaces 2i and spaced parallel surfaces 26 thereon. Vertically aligned apertures 28 extend through ears 20 and bosses 22,.

A knuckle, generally designated 36, having a knuckle nose 38 and a knuckle `tail 4d, is disposed within cavity 16 and between ears 2?. Knuckle 36 presents substantially parallel surfaces il intermedi-ate knuckle nose 3S and knuckle tail 4d. Recesses 42, dened by substantially vertical surfaces 44 and spaced parallel surfaces 45, in-

ZQS Patented Fels. 18, 1964 icc terrupt surfaces 4i and face outwardly thereof. Surfaces 44 are substantially cylindrical as seen in FIGURE l but terminate at 48, forming side openings 'Sil communicating with recesses d2. An aperture 52 extends through knuclde 36 between surfaces i6 and is substantially concentric with surfaces 44. The knuckle is preferably cored `at 53y and 55 to minimize the weight of the knuckle and to substantially reduce casting problems associated with thickened sections.

lAs is clearly shown in FIGURE 2, recesses 42 of the knuckle receive bosses 22 of the coupler head. The knuckle may be inserted between ears 2d by guiding the bosses 22 :through side openings Sil. A pin S4 is inserted through apertures -28 and 52, thereby preventing the knuckle from slipping from between ears 2d through side openings 50. Proper tolerances between the apertures and pin, and surfaces 24 and 44, respectively, of the coupler head and knuckle, are desired, as is well known in the art, so that the forward and rearward movements of the knuckle relative to the coupler head are restricted by engagements of surfaces 24 and dit, not of the pin within the apertures.

As is Well known in the art, knuckle 36 pivots about pin 54 within cavity 16 providing releasable engagement with another knuckle of a mating coupler (not shown). FGURE 1 shows the position of knuckle 35 in the coupler lock position. If the mating coupler with knuckle in `locked position are brought into bung contact with the knuckle 36 when it is in the closed position as shown, the force of the buihng would act on the knuckle substantially as shown by arrowed line S6. However, under such condi-tions, the engaging bosses `and recesses as described heretofore have proved to be insufficient. Failures of the coupler have occurred in various manners: the bosses have een sheared from the ears; the noses have been broken from the knuckles; or the surfaces 24 and 4dform a wedge which forces ears 2t) outwardly and causes subsequent separation thereof from the coupler head.

`Numerous attempts have `been made to correct this weakness but none of them have been completely satisfactory and all have involved substantial modification of knuckle and head structure. The present invention solves the problem by the provision of only a pair of spaced lugs on `the knuckle, arranged for full `face engagement with existing shoulders of the coupler head.

Referring again to the drawings, lugs 6@ are provided on knuckle 3o forwardly of recesses t2 and have concave parti-annular surfaces 6ft thereon. The surfaces 6d are offset from, but have a radius equal to, convex parti-annular surfaces 616 which are formed on the forward shoulders e2 of ears 2d of the coupler head. The surfaces 64 and 66, and the surfaces 2d and 44, form steps forwardly of pin 5d. It is evident that only cylindrical surfaces of equal diameter can contact each other over their f-ull area. Cylindrical surfaces which are concentric to cach other, on the other hand, will contact each other only along their line of tangency. The engagements, therefore, of surfaces de and 66, being full face engagements rather than along a line such as would occur if the surfaces were concentric, thus greatly increase `the bearing areas between `the knuckle and coupler head. Further, the lugs 6@ strengthen the nose 33 of the knuckle, consequently reducing failures thereof.

IIt will be understood that preferably, the clearance between each lug surface 64 and shoulder surface o6 should be equal to the clearance between each recess surface 44 and boss surface 24. However, as a practical matter, manufacturing tolerances prevent this condition from occurring in all instances. The specified tolerances, therefore, are arranged so that the clearance between surfaces 6d and 66 is always equal to or less than the clearance between surfaces 44 and 24.

1 claim:

ln a railway car coupler, a head having a pair of substantially parallel, vertically spaced walls partially defining a cavity, aligned bosses on saidwalls mutually facing each other and extending into said cavity and having forwardly facing arcuately convex surfaces, shoulders projecting from said walls forwardly of said bosses, said shouldes being provided with forwardly `facing arouately convex surfaces, said walls and bosses having axially laligned pin receiving openings therethrough, a pivot pin extending 'through and loosely received in said aligned openings, a knuckle in said cavity, said knuckle having aligned openings loosely receiving said pivot pin, outwardly facing recesses in said knuckle receiving respective associated bosses, said recesses deiining substantially verbical, arcnately concave rearwardly facing surfaces forwardly of said bosses and spaced `from but at times engageable with the forwardly facing surface of che associated boss, outwardly facing lugs on said knuckle defining concave rearwardly facing, parti-annular surfaces spaced from but alt times engageable with said forwardly facing shoulder surfaces, said lug surfaces having a nadius equal to the radius of `the shoulder surfaces so as to provide full face engagement therebetween upon engagement thereof, the clearance bel/tween the rearwardly facing lug surface and forwardly facing shoulder surface being equal to or less than the clearance between the rearwardly facing recess `surface and forwardly facing boss surface.

References Qited. in the ile of this patent UNITED STATES PATENTS 1,696,040 Kelso Dec. 18, 1928 1,848,545 Regan Mar. 8, 1932 1,857,035 Tomlinson May 3, 1932 2,548,479 1Kayler Apr. 10, 1951 2,596,153 Kayler May 13, 1952 

